Gripper



Patented Dec. 22, 1942 UNITED STATES PATENT--`OFFICE GRIPPER Fred C".Eastman, Marblehead, Mass., assigner to United Shoe MachineryCorporation, Flemington, N. J., a corporation of New Jersey ApplicationJuly 30, 1941, Serial No. 404,589 22 claims.v (ol. 12J-101.1)

This invention relates to grippers foruse in shoemachines for pullinguppers to shape them over lasts or other forms. The invention is hereinillustrated as embodied in a gripper particularly designed for use in atoe-lasting ma.

upper maintain a grip of the same force thereon during the upper-pullingoperation, the jaws being closed by spring-operated mechanism the actionof which is unaffected by the pulling'of the upper. While thisconstruction has proved satisfactory under most conditions, it has beenfound that when an upper is unusually heavy and is subjected to acomparatively hard pull the jaws may not hold it securely enough for thebest results in the upper-pulling operation. An object of the presentinvention, accordingly, is

to provide a construction such as to increase theV security with whichthe upper is gripped and held by the jaws without the necessity of usingYa jaw-closing spring which is stronger than is otherwise desirable. Tothis and other ends,

the invention sherein illustrated as embodied*` in a gripper havingmechanism for eiecting relative movement of the jaws to grip the upperprior to the upper-pulling operation and additional mechanism foreiecting further relative movement of the jaws to increase the force oftheir grip on the upper in the course of the upper-pulling operation. Inthe construction shown this additional mechanism acts in response toresistance of the upper to the force of the pull applied thereto, sothat the force with` which the upper is gripped increases with the forceof the pull. As more particularly herein illustrated, the gripping ofthe upper prior to the pull is effected by a cam which is operated bythe usual jaw-closing spring and acts on one of ther jaws alone to moveit into upper-gripping position and to lock it against reverse movement,and the increase in the force of the grip of the jaws on the upper iseiected through' lever mechanism which acts on the other jaw aloneand isoperated by relative movement of parts of the gripper resulting fromresistance of the upper to the force of the pull. In addition to novelfeatures involved in such a combination of mechanisms for effecting'thegripping of the 55 upper and for increasing the force of the gripthereon, novel features are also to be recognized inthe jaw-closingmeansand in the means for increasing the force with which the jaws grip theupper. 4

When a shoe isA positioned bottom upward for vthe ltoe-lasting operationin the machine distate the insertion of theI proper amount of uppermaterialsl in 'the'jaws of the gripper, the jaws are arrangedto 'extendlengthwise of the last at an inclination to the bottom of the last suchthat portions 'of the jaws located comparatively near the end of the toeextend farther toward the upper heightwise of the last than portionsmore remote from the end of the toe. In the construction shown,moreover, the jaws are provided with upper-engaging teeth arranged toextend lengthwise of the margin of the upper and have notches formedonly in portions of the teeth which are located comparatively near theend of the toe. Theportions of the teeth where the notches are locatedgrip the upper more effectively than vother portions, so that the upperis held more securely in locations where it is' comparatively loose onthe last than it is near the portions thereof which have already beenpulled over or lasted. Since the upper near these portions need bepulled but little in the toe-lasting operation,

the jaws may slip more or less thereon while maintaining a more securegrip on the portions nearer the end of the toe where a more effectivepull is required.

The above and other features of the invention, including various noveldetails of construction vand combinations of parts, will now be morepar- Fig. 2 shows a portion of the same `'gripper in elevation, asviewed from the left withlreference to Fig. 1;

Fig. 3 is a view similar to Fig. 1 of a portion of the gripper, butshowing the parts as they appear when gripping and pulling an upper andshowing also other portions of the machine;

Fig. 4 is a view similar to Fig. 2 of the gripper jaws, but illustratingtheir relation to a shoe in the pulling of the upper and showing also aportion of another one of the grippers;

Fig. 5 shows one of the jaws detached; and

Fig. 6 is a plan view illustrating how the several grippers are groupedrelatively to the shoe and to toe-lasting wipers in the above-mentionedmachine.

The machine shown in the above-mentioned Letters Patent is provided withthree grippers for gripping the margin of the toe-end portion of theupper and for pulling the upper automatically in time relation to theoperation of wipers 2 which, after the pulling of the upper, wipe itsmarginal portion inwardly over the insole into lasted position, as shownin Fig. 6, the last and shoe being held by a toe rest 4 (Fig. 4) in :aposition determined by an insole-engaging plate 6 (Figs. 3 and 6). Thegrippers comprise a toeend gripper 8 for pulling the upper at the end ofthe toe and opposite side grippers I0 arranged to act on the upper atthe `sides of the toe. The

present drawing shows, by reference to details of the left-hand sidegripper, how each of the two side grippers may be modified for purposesof this invention, and it is contemplated that the toe-end gripper 8will in most respects be simi-F larly modified in a manner which Will beObvious from the description of the side gripper construction.

The side gripper I8 shown in Figs. 1, 2 and 3 includes a pair ofupper-gripping jaws I2 and vI4 supported by a tubular casingxIS whichcorresponds to the casing 408 shown in the previously mentioned LettersPatent. The jaws, however, are not supported directly on the casing, as

heretofore, but on a jaw carrier I8 having a tubu-` lar portionextending upwardly into an enlarged lower end portion of the casing andloosely mounted therein to permit relative vertical movements of the jawcarrier and the casing between limits determined by a pin 22 mounted inthe casing and a slot 24 formed in the tubular portion 2D of the jawcarrier. The purpose of this lconstruction will be hereinafterdescribed. Clamped on the casing I6 are members 26 and 28 through whichupward movement is imparted to the grip` per to pull the upperheightwise of the last, these members corresponding to the members 524and 526 shown in the above-mentioned Letters Pat ent. Within the casingis a jaw-closing rod similar to a corresponding rod of the priorconstruction and arranged .to be moved upwardly by a spring 32 to effectrelative movement of the jaws to grip the upper, this spring acting on.the lower end of a tubular plunger 34 which is slidingly mounted on theupper end of the rod and carries a pin 3S extending through a slot 38 inthe rod. It will be understood that in moving the rod upwardly the pinengages it at the upper end of the slot. In the construction hereinshown the lower end of the spring 32 lis seated on the jaw carrier I8.When the jaws are in open relation the rod 3!) is held depressed asheretofore by a member in engagement-with the upper end of the plunger34, the plunger acting yieldingly on the rod through the pin 36 and alight 75 spring 42 in the rod. The member 40 corresponds to the member452 shown in the abovementioned Letters Patent.

In the construction herein shown both the jaws I2 and I4 are mounted toswing about a pin 44 supported by the lower ends of two downwardlyextending plates 46 which are formed on the jaw carrier I8 in spacedrelation to each other. The gripping of the upper in response to theupward movement of the rod 30 is effected by swinging movement of thejaw I2, which engages the outer face of the upper, toward the jaw I4.For this purpose, in the construction herein shown, an upwardlyextending tail portion 48 of the jaw I2 is engaged by a cam 50 rotatablymounted on a pin 52 supported by the plates 45 of the jaw carrier I8 andparallel to the pin 44. This cam is provided with a recess 54 to receivethe tail portion of the jaw when the latter is in its open position, asillustrated in Fig. 1, and with a peripheral face 56 for engaging thetail portion of the jaw to impart to the jaw the latter portion of itsswinging movement. This peripheral face of the cam is in such relationto the axis of the pin 52 that when the jaw I2 is in uppergrippingposition, as shown in Fig. 3, the cam serves to lock it effectivelyagainst any reverse swinging movement. For rotating the cam thus tooperate the jaw I2 the rod 30 is connected to the cam by a pair of links58 between which the tail portion 48 of the jaw lies when the jaws arein open relation. For returning the jaw I2 to open position there isprovided a link 60 pivotally connected to the cam 58 and having thereina slot B2 in which lies a pin 64 carried by the tail portion 48 of thejaw. By reference to Figs. 1

-and 3 it will be evident that this slot permits the link to move idlyduring a portion of the return movement of the .cam 50 and that the camacts thereafter through the link to swing the jaw I2 to its fully openposition.

When the jaw I2 is swung as above described to grip the upper, nocorresponding movement of the jaw i4 toward the jaw I2 takes place, and,accordingly, the gripping of the upper is effected by the movement ofthe jaw I2 alone. The jaw I4, however, is not xed to the jaw carrier I8,but as previously suggested is capable of swinging about the pin 44. Forcontrolling the jaw I4 there are provided two levers 66 mounted at theouter sides of the plates 46 of the jaw carrier I8 to swing about thepreviously mentioned pin 52, the right-hand ends of these levers, as theparts are viewed in Figs. 1 and 3, being connected by links 63 to thejaw I4. Only one of these links is visible in the drawing, since theylie in the same vertical planes as the plates 45 oi the jaw carrier. Theother ends of the levers 66 are connected by links 'I0 to the previouslymentioned pin 22 which is mounted in the casing I6. It will thus be seenthat no swinging movement of the jaw I 4 about the pin 44 can take placeexcept as accompanied by relative vertical movement of the casing i3 andthe jaw carrier I8. In the pulling of the upper heightwise of the last,as more fully hereinafter explained, there is a tendency to move thecasing upward relatively to the jaw carrier and thereby to move the jawI4 toward the jaw I2 to increase the force with which the upper isgripped by the jaws. It will be understood that the two levers 66 have asingle function, the duplicate construction being provided simply forgreater strength .and better balance.

By reference to Fig. 4 it will be observed that the jaws of the gripperare inclined somewhat relatively to the bottom of the last in a downwarddirection toward the end of the toe. The reason for this construction isthat when a shoe is presented to the machine the margin of the upperwhich is to be engaged by the gripper at each side of the toe usuallyoccupies a position somewhat lower near the end of the toe than fartherheelwardly, as hereinbefore explained. The inclination ofthe jaws in themanner illustrated facilitates the insertion of the proper amount ofupper in the jaws throughout the length of the jaws. It will also beobserved by reference particularly to Figs. 1 and 5 that the jaw I4 isprovided with two teeth 12 arranged to extend lengthwise of the marginof the upper and that the jaw I2 has a single similarly extending tooth14 arranged to force the upper into the uspace between the two teeth 12.In portions of the several teeth which are located com-L paratively nearthe end of the toe there are provided notches 16 which increase theeiectiveness of the grip of those portions of the teeth on the upper ascompared with the portions which are Without such notches. Accordingly,the gripper holds the upper more securely in locations where it iscomparatively loose on the last prior to the toe-lasting operation thanadjacent to portions of the upper which have already been pulled over orlasted and where, therefore, but little further pull is required.

The manner of operation of the novel gripper will now be brieflysummarized. Initially the member 40 is in the position illustrated inFig. l

and holds the jaw-closing rod 30 depressed with" the jaws of the gripperin open relation, the jaw carrier I8 being held by this member, throughthe spring 32, in its lowest position determined by engagement of thepin 22 with the tubular portion 20 of the carrier at the upper end ofthe slot 24. It will be understood that at this time the gripper jawsoccupy a lower position than in Fig. 4, their downward inclinationtoward the end of the toe being such as to facilitate the`A insertion ofthe proper amount of upper ma-i terials between them near the end of thetoe as well as in other locations. When in the operation of the machinethe member 40 is moved upwardly and the jaw-closing rod 30 is accord-` Aingly lifted by the spring 32, the rod acts through the links 58 toswing the cam 50 from its starting position (Fig. l) to the position inwhich it is shown in Fig. 3, the cam acting on the tail portion 48 ofthe jaw I2 to swing this jaw toward the jaw I4 into position to grip theupper.

Near the end of its movement the jaw I2 by its pressure on the margin ofthe upper causes the jaw I4 to swing a short distance in the samedirection as the jaw I2. The effect of this movement of the jaw I4 is toswing the levers 66 about their connections with the links 18 and thusto lift the jaw carrier I8 relatively to the casing I6 to space theupper end of the slot 24 from the pin 22. This action is facilitated byreason of the fact that after the upward movement of the member 40 awayfrom the plunger 34 there is no longer any tendency to force the jawcarrier I8 in a downward direction relatively to the casing I6 throughthe spring 32.

Thereafter, in the course of the operation of the to the jaw carrier I8through the links 10 and the levers 6B connected by the links 68 to thejaw I4, and in so far as this force is effective to lift the jaw carrierit is also effective on the jaw I4 to increase the force with which theupper is gripped by the jaws, the jaw I2 being held positively by thecam 50 against reverse movement. In other words, the mechanismconnecting the casing I6 to the jaw I4 acts in response to resistance ofthe upper to the force of the pull applied thereto, by reason of thetendency of the casing to move upward relatively to the jaw carrier I8,to increase the force with which the upper is gripped by the jaws.Accordingly, insurance is afforded that if an upper is unusually heavyand is subjected to a comparatively hard pull the jaws will hold itsecurely enough for satisfactory results in the lasting operation. Byreason of the construction of the jaws,'however, they may slip more orless near the end of the upper-pulling operation on portions of theupper comparatively remote from the end of the toe while maintaining amore effective grip on portions located nearer the end of the toe, ashereinbefore explained.

Having described the invention, what I claim as new and desire to secureby Letters Patent of the United States is:

1. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper includingjawclosing mechanism for eiecting relative movement of said jaws to gripthe upper prior to the upper-pulling operation and including alsoadditional mechanism for thereafter effecting further relative movementof the jaws in the course of the upper-pulling operation to increase theforce of their grip on the upper.

2. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper includingjawclosing mechanism for effecting relative movement of said jaws togrip the upper prior to the upper-pulling operation and including alsoadditional mechanism arranged to act thereafter in response toresistance of the upper to the force of the pull applied thereto toeffect further relative movement of the jaws to increase the force oftheir grip on the upper.

3. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper including ajaw carrier supporting said jaws, means supported on said jaw carrierfor eiecting relative movement of the jaws to grip the upper prior tothe upper-pulling operation, and additional means also supported on saidjaw carrier for thereafter effecting further relative movement of thejaws in the course' of the upper-pulling operation to increase the forceof their grip on the upper.

4. In a shoe machine, a gripper'having a pair of jaws for gripping anupper between them and ojf jaws for gripping an upper between them andfor pulling the upper, means for moving one of Said jaws alone towardthe other jaw to grip the upper prior to the upper-pulling operation,and additional means for thereafter moving said other jaw alone towardthe iirst-n'amed jaw in the course of the upper-pulling operation toincrease the force with which the upper is gripped by the jaws.

G. In a shoe machine, a gripper having a pair.

of jaws for gripping an upper between them and for pulling the upper,means for moving one of said jaws alone toward the other jaw to grip theupper prior to the upper-pulling operation, and mechanism arranged toact thereafter in response to resistance of the upper to the force ofthe pull applied thereto to move said other jaw toward the rst-named jawand thus to increase the force with which the upper is gripped by thejaws.

7. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, mechanism for moving oneof said jaws alone toward the other jaw to grip Vthe upper and forlocking it positively against reverse movement, and additional mechanismarranged to act thereafter in response to resistance of the upper to theforce of the pull applied thereto to move said other jaw toward thefirstnamed jaw and thus to increase the force with which the upper isgripped by the jaws.

8. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, a cam arranged to act onone of said jaws alone to move it toward the other jaw to grip the upperand then to hold it against reverse movement, and mechanism arranged toact thereafter in the course of the upper-pulling operation to move theother jaw toward said cam-operated jaw and thus to increase the forcewith which the upper is gripped by the jaws.

9. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, a jaw carrier supportingsaid jaws, means supported on said jaw carrier for moving one of thejaws alone toward the other jaw to grip the upper prior to theupperpulling operation, and additional means also supported on said jawcarrier for thereafter moving said other jaw toward the rst-named jaw inresponse to resistance of the upper to the force of the pull appliedthereto to increase the force with which the upper is gripped by thejaws.

10. In a shoe machine, a gripper having a Ipair of jaws for gripping anupper between them and for pulling the upper, said gripper including ajaw carrier supporting said jaws, a Cam rotatably supported on said jawcarrier and arranged to act on one of said jaws to move it toward theother jaw to grip the upper, spring-operated means for thus operatingsaid cam prior to the upper-pulling operation, and mechanism alsosupported on said jaw carrier for thereafter moving said other jawtoward the cam-operated jaw in the course of the upper-pulling operationto increase the force with which the upper is gripped by the jaws.

11. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper includingparts relatively movable in response to resistance of the upper to theforce of the pull applied thereto, mechanism for moving one of said jawsalone toward the other jaw to grip .the upper prior to the upper-pullingoperation, and additional mechanism arranged to be operated by therelative movement of said parts in the course of the upper-pullingoperation to move said other jaw toward the first-named jaw to increasethe force with which the upper is gripped kby the jaws.

12. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper including ajaw carrier supporting said jaws and also a member supporting said jawcarrier, said carrier and member being relatively movable in response toresistance of the upper to the force of the pull applied thereto, meanssupported on said jaw carrier for effecting relative movement of thejaws to grip the upper prior to the upper-pulling operation, andadditional means also supported on the jaw carrier and connected to saidmember for thereafter moving one of the jaws toward the other toincrease the force of their grip on the upper in response to therelative movement of said carrier and member in the upper-pullingoperation.

13. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper including ajaw carrier supporting said jaws and also a member supporting said jawcarrier, said carrier and member being relatively movable in response toresistance of the upper to the force of the -pull applied thereto, a camsupported on said jaw carrier for moving one of the jaws toward theother to grip the upper prior to the upper-pulling operation, a leveralso supported on said jaw carrier and connected to said other jaw, andmeans connecting said lever and member for operating the lever to movesaid other jaw tow-ard the first-named jaw to increase the force withwhich the upper is gripped by the jaws in response to the relativemovement of said carrier and member in the upper-pulling operation.

14. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper includingmembers relatively movable in response to resistance of the `upper tothe force of the pull applied thereto and on one of which members thejaws are supported, a lever supported on said last-named member formoving one of the jaws toward the other to increase the force with whichthe upper is gripped by the jaws, and means for thus operating saidlever by the relative movement of said members in the upper-pullingoperation.

15. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, said gripper includingmembers relatively movable in response to resistance of the upper to theforce of the pull applied thereto and on one of which members the jawsare supported, a lever fulcrumed between its opposite ends on saidlast-named member, a link connecting one end of-said lever to one of thejaws for moving that jaw toward the other [by the lever to increase theforce with which the upper is gripped by the jaws, and a link connectingthe other end of the lever to the other member for thus operating thelever lby the relative movement of said members in the upperpullingoperation.

16. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, a member on which saidjaws are supported, a cam rotatably supported on said member for movingone of the jaws toward the other to grip the upper by engagement of the-cam with the jaw thus moved, and a spring-operated member for rotatingsaid cam.

17. In a shoe machine, .a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, a member on which saidjaws are supported, a cam rotatably supported on said member for movingone of the jaws toward the other to grip the upper, a spring-operatedrod, and a link connecting said rod Ito the cam for rotating the cam bythe rod.

18. In `a shoe machine, a gripper having a pair of jaws forgripping anupper between them and for pulling the upper, a member on which saidjaws are supported, a cam rotatably supported on said member forswinging one of the jaws toward the other to grip the upper by rotationof the cam about an aXis substantially parallel to the axis of theswinging jaw, and spring-operated means for thus rotating said cam.

19. In a shoe machine, a gripper having a pair of jaws for gripping anupper between them and for pulling the upper, a jaw carrier supporting`said jaws and movable with them to pull the upper, a cam supported onsaid jaw carrier for rotation to move one of the jaws toward the otherto grip the upper, and a spring arranged thus to rotate said cam andmovable thereafter bodily with the jaws in the pulling of the upper.

20. In a shoe machine, the combination with means for positioning a lastand shoe for the lasting of the toe-end portion of the upper, of

grippers for gripping and pulling the upper a-t the opposite sides ofthe toe respectively, each of said grippers having a pair ofupper-gripping jaws arranged to extend lengthwise of the last at such aninclination to the bottom of the last as to cause portions of the jawswhich engage the upper comparatively near the end of the toe to extendfarther toward the upper heightwise of the last than portions of thejaws more remote from the end of the toe.

21. In a shoe machine, the combination with means for positioning a lastand shoe for the lasting of the toe-end portion of the upper, ofgrippers arranged to pull 4the upper at the cpposite sides of the toerespectively and each having a pair of jaws for gripping the upperbetween them, portions of said jaws which are located comparatively nearthe end of the toe being so formed as to grip the upper more securelythan portions more remote from the end of the toe.

22. In a shoe machine, the combination with means for positioning a lastand shoe for the lasting of the toe-end portion of the upper, ofgrippers arranged to pull the upper at the `opposite sides of the toerespectively and each having a pair of jaws for gripping the upperbetween them, said jaws being provided with upper-engaging teethextending lengthwise of the margin of the upper and the teeth havingnotches formed only in portions thereof which are located comparativelynear the end of the toe.

FRED C. EASTMAN.

